Assume that a secure file sharing system needs to be designed. Consider two users: Alice and Bob. Using the secure file sharing system, Alice would like to share a file $$file$.$txt$$ to Bob. Answer the following questions: a$)$ The file $$file$.$txt$$ should be encrypted by Alice before sending it to Bob. Which cryptography technique $($Symmetric or Asymmetric$)$ would you use for the encryption? Justify your answer.